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                                                                   EXHIBIT 4.2.4


[COMERICA LOGO]    GUARANTY

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As of March 4, 1998, the undersigned, for value received, unconditionally and
absolutely guarantee(s) to Comerica Bank ("Bank"), a Michigan banking
corporation, payment when due, whether by stated maturity, demand, acceleration
or otherwise, of all existing and future indebtedness ("Indebtedness") to the
Bank of Newcor, Inc., a Delaware corporation ("Borrower"). Indebtedness includes
without limit any and all obligations or liabilities of the Borrower to the
Bank, whether absolute or contingent, direct or indirect, voluntary or
involuntary, liquidated or unliquidated, joint or several, known or unknown; any
and all indebtedness, obligations or liabilities for which Borrower would
otherwise be liable to the Bank were it not for the invalidity, irregularity or
unenforceability of them by reason of any bankruptcy, insolvency or other law or
order of any kind, or for any other reason; any and all amendments,
modifications, renewals and/or extensions of any of the above; and all costs of
collecting Indebtedness, including, without limit, attorney fees. Any reference
in this Guaranty to attorney fees shall be deemed a reference to reasonable
fees, charges, costs and expenses of both in-house and outside counsel and
paralegals, whether or not a suit or action is instituted, and to court costs if
a suit or action is instituted, and whether attorney fees or court costs are
incurred at the trial court level, on appeal, in a bankruptcy, administrative or
probate proceeding or otherwise. All costs shall be payable immediately by the
undersigned when incurred by the Bank, without demand, and until paid shall bear
interest a the highest per annum rate applicable to any of the Indebtedness, but
not in excess of the maximum rate permitted by law.

1.   LIMITATION: The total obligation of the undersigned under this Guaranty is
     UNLIMITED unless specifically limited in the Additional Provisions of this
     Guaranty, and this obligation (whether unlimited or limited to the extent
     specified in the Additional Provisions) shall include, IN ADDITION TO any
     limited amount of principal guaranteed, all interest on that limited
     amount, and all costs incurred by the Bank in collection efforts against
     the Borrower and/or the undersigned or otherwise incurred by the Bank in
     any way relating to the Indebtedness, or this Guaranty, including without
     limit attorney fees. The undersigned agree(s) that (a) this limitation
     shall not be a limitation on the amount of Borrower's Indebtedness to the
     Bank; (b) any payments by the undersigned shall not reduce the maximum
     liability of the undersigned under this Guaranty unless written notice to
     that effect is actually received by the Bank at, or prior to, the time of
     the payment; and (c) the liability of the undersigned to the Bank shall at
     all times be deemed to be the aggregate liability of the undersigned under
     this Guaranty and any other guaranties previously or subsequently given to
     the Bank by the undersigned and not expressly revoked, modified or
     invalidated in writing.

2.   NATURE OF GUARANTY: This is a continuing Guaranty of payment and not of
     collection and remains effective whether the Indebtedness is from time to
     time reduced and later increased or entirely extinguished and later
     reincurred. The undersigned deliver(s) this Guaranty based solely on the
     undersigned's independent investigation of (or decision not to investigate)
     the financial condition of Borrower and is (are) not relying on any
     information furnished by the Bank. The undersigned assume(s) full
     responsibility for obtaining any further information concerning the
     Borrower's financial condition, the status of the Indebtedness or any other
     matter which the undersigned may deem necessary or appropriate now or
     later. The undersigned knowingly accept(s) the full range of risk
     encompassed in this Guaranty, which risk includes, without limit, the
     possibility that Borrower may incur Indebtedness to the Bank after the
     financial condition of the Borrower, or the Borrower's ability to pay debts
     as they mature, has deteriorated.

3.   APPLICATION OF PAYMENTS: The undersigned authorize(s) the Bank, either
     before or after termination of this Guaranty, without notice to or demand
     on the undersigned and without affecting the undersigned's liability under
     this Guaranty, from time to time to: (a) apply any security and direct the
     order or manner of sale; and (b) apply payments received by the Bank from
     the Borrower to any indebtedness of the Borrower to the Bank, in such order
     as the Bank shall determine in its sole discretion, whether or not this
     indebtedness is covered by this Guaranty, and the undersigned waive(s) any
     provision of law regarding application of payments which specifies
     otherwise. The undersigned agree(s) to provide to the Bank copies of the
     undersigned's financial statements upon request.

4.   SECURITY: The undersigned grant(s) to the Bank a security interest in and
     the right of setoff as to any and all property of the undersigned now or
     later in the possession of the Bank. The undersigned further assign(s) to
     the Bank as collateral for the obligations of the undersigned under this
     Guaranty all claims of any nature that the undersigned now or later has
     (have) against the Borrower (other than any claim under a deed of trust or
     mortgage covering California real property) with full right on the part of
     the Bank, in its own name or in the name of the undersigned, to collect and
     enforce these claims. The undersigned agree(s) that no security now or
     later held by the Bank for the payment of any Indebtedness, whether from
     the Borrower, any guarantor, or otherwise, and whether in the nature of a
     security interest, pledge, lien, assignment, setoff, suretyship, guaranty,
     indemnity, insurance or otherwise, shall affect in any manner the
     unconditional obligation of the undersigned under this Guaranty, and the
     Bank, in its sole discretion, without notice to the undersigned, may
     release, exchange, enforce and otherwise deal with any security without
     affecting in any manner the unconditional obligation of the undersigned
     under this Guaranty. The undersigned acknowledge(s) and agree(s) that the
     Bank has no obligation to acquire or perfect any lien on or security
     interest in any asset(s), whether realty or personalty, to secure payment
     of the Indebtedness, and the undersigned is (are) not relying upon any
     asset(s) in which the Bank has or may have a lien or security interest for
     payment of the Indebtedness.

5.   OTHER GUARANTORS: If any Indebtedness is guaranteed by two or more
     guarantors, the obligation of the undersigned shall be several and also
     joint, each with all and also each with any one or more of the others, and
     may be enforced at the option of the Bank against each severally, any two
     or more jointly, or some severally and some jointly. The Bank, in its sole
     discretion, may release any one or more of the guarantors for any
     consideration which it deems adequate, and may fail or elect not to prove a
     claim against the estate of any bankrupt, insolvent, incompetent or
     deceased guarantor; and after that, without notice to any guarantor, the
     Bank may extend or renew any or all Indebtedness and may permit the
     Borrower to incur additional Indebtedness, without affecting in any manner
     the unconditional obligation of the remaining guarantor(s). The undersigned
     acknowledge(s) that the effectiveness of this Guaranty is not conditioned
     on any or all of the indebtedness being guaranteed by anyone else.

6.   TERMINATION: Any of the undersigned may terminate their obligation under
     this Guaranty as to future Indebtedness (except as provided below) by (and
     only by) delivering written notice of termination to an officer of the Bank
     and receiving from an officer of the Bank written acknowledgement of
     delivery; provided, however, the termination shall not be effective until
     the opening of business on the fifth (5th) day ("effective date") following
     written acknowledgement of delivery. Any termination shall not affect in
     any way the unconditional obligations of the remaining guarantor(s),
     whether or not the termination is known to the remaining guarantor(s). Any
     termination shall not affect in any way the unconditional obligations of
     the terminating guarantor(s) as to any Indebtedness existing at the
     effective date of termination or any Indebtedness created after that
     pursuant to any commitment or agreement of the Bank or pursuant to any
     Borrower loan with the Bank existing at the effective date of termination
     (whether advances or readvances by the Bank after the effective date of
     termination are optional or obligatory), or any modifications, extensions
     or renewals of any of this Indebtedness,

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     whether in whole or in part, and as to all of this Indebtedness and
     modifications, extensions or renewals of it, this Guaranty shall continue
     effective until the same shall have been fully paid. The Bank has no duty
     to give notice of termination by any guarantor(s) to any remaining
     guarantor(s). The undersigned shall indemnify the Bank against all claims,
     damages, costs and expenses, including, without limit, attorney fees,
     incurred by the Bank in connection with any suit, claim or action against
     the Bank arising out of any modification or termination of a Borrower loan
     or any refusal by the Bank to extend additional credit in connection with
     the termination of this Guaranty.

7.   REINSTATEMENT: Notwithstanding any prior revocation, termination, surrender
     or discharge of this Guaranty (or of any lien, pledge or security interest
     securing this Guaranty) in whole or in part, the effectiveness of this
     Guaranty, and of all liens, pledges and security interests securing this
     Guaranty, shall automatically continue or be reinstated in the event that
     any payment received or credit given by the Bank in respect of the
     Indebtedness is returned, disgorged or rescinded under any applicable state
     or federal law, including, without limitation, laws pertaining to
     bankruptcy or insolvency, in which case this Guaranty, and all liens,
     pledges and security interests securing this Guaranty, shall be enforceable
     against the undersigned as if the returned, disgorged or rescinded payment
     or credit had not been received or given by the Bank, and whether or not
     the Bank relied upon this payment or credit or changed its position as a
     consequence of it. In the event of continuation or reinstatement of this
     Guaranty and the liens, pledges and security interests securing it, the
     undersigned agree(s) upon demand by the Bank, to execute and deliver to the
     Bank those documents which the Bank determines are appropriate to further
     evidence (in the public records or otherwise) this continuation or
     reinstatement, although the failure of the undersigned to do so shall not
     affect in any way the reinstatement or continuation. If the undersigned
     do(es) not execute and deliver to the Bank upon demand such documents, the
     Bank and each Bank officer is irrevocably appointed (which appointment is
     coupled with an interest) the true and lawful attorney of the undersigned
     (with full power of substitution) to execute and deliver such documents in
     the name and on behalf of the undersigned.

8.   WAIVERS: The undersigned waive(s) any right to require the Bank to: (a)
     proceed against any person or property; (b) give notice of the terms, time
     and place of any public or private sale of personal property security held
     from the Borrower or any other person, or otherwise comply with the
     provisions of Section 9-504 of the Michigan or other applicable Uniform
     Commercial Code; or (c) pursue any other remedy in the Bank's power. The
     undersigned waive(s) notice of acceptance of this Guaranty and presentment,
     demand, protest, notice of protest, dishonor, notice of dishonor, notice of
     default, notice of intent to accelerate or demand payment of any
     Indebtedness, any and all other notices to which the undersigned might
     otherwise be entitled, and diligence in collecting any Indebtedness, and
     agree(s) that the Bank may, once or any number of times, modify the terms
     of any Indebtedness, compromise, extend, increase, accelerate, renew or
     forbear to enforce payment of any or all Indebtedness, or permit the
     Borrower to incur additional Indebtedness, all without notice to the
     undersigned and without affecting in any manner the unconditional
     obligation of the undersigned under this Guaranty.

     The undersigned unconditionally and irrevocably waive(s) each and every
     defense and setoff of any nature which, under principles of guaranty or
     otherwise, would operate to impair or diminish in any way the obligation of
     the undersigned under this Guaranty, and acknowledge(s) that each such
     waiver is by this reference incorporated into each security agreement,
     collateral assignment, pledge and/or other document from the undersigned
     now or later securing this Guaranty and/or the Indebtedness, and
     acknowledge(s) that as of the date of this Guaranty no such defense or
     setoff exists.

9.   WAIVER OF SUBROGATION: The undersigned waive(s) any and all rights (whether
     by subrogation, indemnity, reimbursement, or otherwise) to recover from the
     Borrower any amounts paid by the undersigned pursuant to this Guaranty
     until the Indebtedness has been paid in full.

10.  SALE/ASSIGNMENT: The undersigned acknowledge(s) that the Bank has the right
     to sell, assign, transfer, negotiate, or grant participations in all or any
     part of the Indebtedness and any related obligations, including, without
     limit, this Guaranty, without notice to the undersigned and that the Bank
     may disclose any documents and information which the Bank now has or later
     acquires relating to the undersigned or to the Borrower in connection with
     such sale, assignment, transfer, negotiation, or grant. The undersigned
     agree(s) that the Bank may provide information relating to this Guaranty or
     relating to the undersigned to the Bank's parent, affiliates, subsidiaries
     and service providers.

11.  GENERAL: This Guaranty constitutes the entire agreement of the undersigned
     and the Bank with respect to the subject matter of this Guaranty. No
     waiver, consent, modification or change of the terms of the Guaranty shall
     bind any of the undersigned or the Bank unless in writing and signed by the
     waiving party or an authorized officer of the waiving party, and then this
     waiver, consent, modification or change shall be effective only in the
     specific instance and for the specific purpose given. This Guaranty shall
     inure to the benefit of the Bank and its successors and assigns and shall
     be binding on the undersigned and the undersigned's heirs, legal
     representatives, successors and assigns including, without limit, any
     debtor in possession or trustee in bankruptcy for any of the undersigned.
     The undersigned has (have) knowingly and voluntarily entered into this
     Guaranty in good faith for the purpose of inducing the Bank to extend
     credit or make other financial accommodations to the Borrower. If any
     provision of this Guaranty is unenforceable in whole or in part for any
     reason, the remaining provisions shall continue to be effective. THIS
     GUARANTY SHALL BE GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE INTERNAL
     LAWS OF THE STATE OF MICHIGAN, WITHOUT REGARD TO CONFLICT OF LAWS
     PRINCIPLES.

12.  HEADINGS: Headings in this Agreement are included for the convenience of
     reference only and shall not constitute a part of this Agreement for any
     purpose.

13.  ADDITIONAL PROVISIONS:  None.


14.  JURY TRIAL WAIVER: THE UNDERSIGNED AND BANK ACKNOWLEDGE THAT THE RIGHT TO
     TRIAL BY JURY IS A CONSTITUTIONAL ONE, BUT THAT IT MAY BE WAIVED. EACH
     PARTY, AFTER CONSULTING (OR HAVING HAD THE OPPORTUNITY TO CONSULT) WITH
     COUNSEL OF THEIR CHOICE, KNOWINGLY AND VOLUNTARILY, AND FOR THEIR MUTUAL
     BENEFIT WAIVES ANY RIGHT TO TRIAL BY JURY IN THE EVENT OF LITIGATION
     REGARDING THE PERFORMANCE OR ENFORCEMENT OF, OR IN ANY WAY RELATED TO, THIS
     GUARANTY OR THE INDEBTEDNESS.



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IN WITNESS WHEREOF, Guarantor(s) has (have) signed and delivered this Guaranty
the day and year first written above.

                                       GUARANTOR(S): GRAND MACHINING COMPANY
WITNESSES (as to all signatures):

_________________________________         By:___________________________________
SIGNATURE OF

                                       Its:_____________________________________


_________________________________         By:___________________________________
SIGNATURE OF

                                       Its:_____________________________________
_________________________________
                                       DECO TECHNOLOGIES, INC.

_________________________________
                                       By:______________________________________

_________________________________
                                         Its:___________________________________

_________________________________
                                       By:______________________________________

_________________________________
                                         Its:___________________________________

                                       DECO INTERNATIONAL, INC.
_________________________________

                                       By:______________________________________

_________________________________
                                         Its:___________________________________

_________________________________
                                       By:______________________________________


                                         Its:___________________________________

                                       TURN-MATIC, INC.


                                       By:______________________________________


                                         Its:___________________________________

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                                       By:______________________________________
__________________________________

                                         Its:

                                       GUARANTOR'S ADDRESS:
__________________________________
                                       1825 S. Woodward, Suite 240
                                       Bloomfield Hills, Michigan 48302

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